Dynamic Solenoid Drive Duty Cycle Adjustment

Abstract

The performance of a solenoid drive liquid pump can be very dependent on the magnitude and stability of an input voltage, with non-ideal input power resulting in loss of efficiency and potential damage to the pump. Pulse width of drive signals provided to the pump, which cause solenoids to alternately energize to move liquid through the pump, may be adjusted in duration in order to compensate for non-ideal input voltage. A drive control module of the pump gathers voltage information, determines an improved pulse width based upon that voltage information, and then provides drive signals based upon the improved pulse width. Operating in this manner, a pump can operate at or near peak efficiency despite both significant variances in input voltage and non-sinusoidal input voltage, and without customized components or adapters.

Description

CROSS REFERENCE TO RELATED INFORMATION[0001]This application claims the benefit of U.S. Provisional Patent Application No. 62 / 558,486, filed Sep. 14, 2017, titled Dynamic Solenoid Drive Duty Cycle Adjustment, the contents of which are hereby incorporated herein in its entirety.TECHNICAL FIELD[0002]The present disclosure is directed to a system and method for dynamically adjusting drive duty cycle to account for varying conditions of power input to a pump.BACKGROUND OF THE INVENTION[0003]Positive displacement solenoid drive pumps operate by energizing a coil to create a magnetic field that moves a shaft within the pump. The movement of the shaft within a chamber of the pump can displace liquids or gases within chamber by, for example, the movement of a plunger or diaphragm attached to the shaft drawing liquid into the pumping chamber through an inlet check valve or forcing liquid from the pumping chamber through an outlet check valve. The displacement caused by the plunger or diaphra...

AI Technical Summary

Benefits of technology

The patent text describes a method for determining an appropriate pulse width for a pump, which can automatically or manually adapt to various power sources and conditions without needing specialized hardware. This method can increase efficiency and longevity of the pump while minimizing the impact on cost.

Problems solved by technology

This is caused by the expansion and retraction of a diaphragm or displacement of the plunger within the chamber, which changes the overall volume of the chamber, thereby creating areas of low pressure or forcing liquid from the chamber.

In addition to variations in stable input voltage, some power sources may have noisy or unstable power input resulting in non-sinusoidal voltage waveforms.

These solutions may increase the cost of designing, developing, and certifying a pump (e.g., multiple pumps must be designed and separately certified for each scenario versus designing a single universal pump), as well as manufacturing, selling and supporting a pump (e.g., manufacturers or suppliers must build a different pump for each region and scenario, market them differently, provide different manuals and support services, for each, etc.).

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